Dura-Vent Pellet Vent Fireplace 3 Inch Zincalume Swivel Elbow constructed by laser-welded, double-wall pipe with an inner wall of .012" stainless steel and a .018" laser-welded galvalume outer wall. It has no required gaskets or sealants to achieve leak resistant connections. Dura-Vent elbow is used to attach to appliance outlet allowing for easy pipe connection. It is a venting system designed for stoves and inserts that use wood pellets and oil fuel. Dura-Vent elbow is a venting system designed for stoves and inserts that use wood pellets and oil fuel.